# Relationship history for MSHA mine 1511672

Current hierarchy: **Smith Bill G → Bill G Coal Company Inc → No 1 Mine**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Ousley Cecil D → No 1 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Crystal Star Coal Company Inc → No 1 Mine; 1978-11-01 to 1980-01-29; source msha-controller-operator-history
- **controller_controls_mine:** Bowling Charles D Et Al → No 1 Mine; 1978-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bowling Charles D Et Al → Crystal Star Coal Company Inc; 1978-11-01 to 1980-01-29; source msha-controller-operator-history
- **operator_operates_mine:** Wolf Pen Coals Inc → No 1 Mine; 1980-01-30 to 1980-08-03; source msha-controller-operator-history
- **controller_controls_operator:** Ousley Cecil D → Wolf Pen Coals Inc; 1980-01-30 to 1980-08-03; source msha-controller-operator-history
- **operator_operates_mine:** Bill G Coal Company Inc → No 1 Mine; 1980-08-04 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Smith Bill G → No 1 Mine; 1980-08-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Smith Bill G → Bill G Coal Company Inc; 1980-08-04 to current/open; source msha-controller-operator-history